CO2 tank refill, how long did yours last?

[cemantic]

Hello,

I haven't been here for a while.  The tank is a constant jungle and needs trimming but the CO2 has worked great.  Too good possibly?  Nah ... all the fish seem to love the environment.

My question is for people who are using a CO2 injection system.  I have a 10 lb tank, Sumo regulator, ideal needle valve, bubble counter and a solenoid.  The 10 lb CO2 tank was at 850 when first installed and has been running since august 15 approx so about 9 months.  It slowly dropped in pressure then about a week ago it dropped to almost nothing.  CO2 appeared to still be coming out at the right rate but I turned it off and just got the tank refilled today.  I will replace it tonight after work.

What have other people experienced as far as how long a tank lasts for?

[fischkopp]

Nine months sounds like a pretty long time. I have to refill a 10lb bottle after 4-6 months, but I am running more than one tank per rig. It all depends on how much light is present and how many plants you need to supply.

[charlie]

I`m with Fischkopp here, 9 mths - you are in the happy zone approx. $2.75 per mth. Your lights will dictate the amount of co2 injected, more lights faster growth rate =more co2 required.

[cemantic]

Sorry Charlie, put it in the wrong place.

So I guess I am doing okay.  I haven't checked any levels once I was satisfied that the CO2 was at about 30.  It cost me $26.55 to fill it at Davidson Fire Extinguishers.  They were great and close to home.  I went in there this morning thinking I would have to leave it but they filled it right away and I was home less the a half hour later.

In a moment of weakness and it was a useful thing I bought a Cal Aqua Labs' "Double Check"  http://www.calaqualabs.com/Doublecheck.html  It worked well at first but the openings to add the indicator and baseline reference solutions were so narrow that it was impossible to clean them and add more of the fluids.  I will break it our again and hopefully be able to use it.  I washed it and left it to dry months ago but it was never 100% clean.

I am a little concerned about starting the CO2 back up again.  It has not had any since thursday.  I don't want to blow the PH and harm the fish.  The needle valve is set where it was, I will put it back to 20 lbs where it was and I should be okay.  Any suggestions or comments?